1. Field of the Invention
The present invention relates to an antenna structure, and a wave clock having the antenna structure, and a method for manufacturing the antenna structure.
2. Description of the Prior Art
It has been proposed that plural sheets of foils having the same shape and size, which comprise an amorphous soft magnetic material, are laminated to form a laminated body, and the laminated body is covered with an electrically insulative film, and then a wire is wound thereon to form a coil, thereby an antenna structure for a wave clock is manufactured (JP-A-2003-110341).
However, when the antenna structure having a generally straight and rod-like shape is tried to be received in a typically circular, clock case, it is hard to be received efficiently.
It is also proposed that such an antenna structure is arcuately formed.
However, even in the case of the proposed antenna structure, when the arcuate antenna is disposed close to an inner circumferential surface of a circular case, ends and ears of the antenna where magnetic flux for detection comes in and out are situated close to the case similarly as the center of the antenna formed by winding the coil, as a result effective reception of an electric wave may be obstructed by the case. If the straight antenna structure is tried to be received into the case, the problem is more significant.
The invention, which was made in the light of the above points, aims to provide an antenna structure which is received in a case in a condition that an occupied space is minimized and allows reception of an electric wave at excellent sensitivity, and a wave clock having the antenna structure, and a method for manufacturing the antenna structure.